avrcp: track transaction labels for registered events

avrcp: use packet handler in avrcp for both roles and dispatch to hihger layer

avrcp: add packet handler registration for target and controller in avrcp

avrcp: use role for connection lookup

avrcp: remove connections from context, use one list of connections in avrcp. connection lookup is not yet extended to check the role

avrcp: add role to connection

avrcp: remove browsing flag from create SDP record as it is pat of supported features

avrcp: introduce enum for suported features

avrcp_target: AVRCP_MEDIA_ATTR_NONE + 1 = AVRCP_MEDIA_ATTR_ALL

avrcp: fix compilation for c++

GAP: security level for Classic protocols (asides SDP) raised to 2 (encryption)

avrcp target: reject invalid pid

avrcp target: reject incorect pid

avrcp target: remove unused vars, fix set absolute volume; on invalid param, send the current volume

avrcp browsing target: send response to get total num of items; remove printf from library

avdtp target: fix parsing vendor dependent cmds

avrcp target: fix compile errors, draft get folder items

avrctp browsing target: start addr player changed, get folder items

avrcp target: remove unused variable

avrcp browsing target: create browsing connection

avrcp target: implement passthrough 3 & 4

avrcp: set addressed player, get total num items

avrcp target: remove wrong break

a2dp source: fix cid chack on incoming connection

avrcp browsing: change API for folder/media browsing